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Author Topic: 4 pin wiring harness to my 7 pin trailer plug Problem  (Read 29105 times)

jaxbuckeye

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4 pin wiring harness to my 7 pin trailer plug Problem
« on: November 30, 2012, 09:45:51 AM »
My new (to me) Viking PUP trailer has a 7-pin "round" electrical connection including electric brakes.  My vehichle just has the standard 4-pin flat rectangle receiver on its hitch.  I bought an adapter for it but the trailer lights still won't work.  I've double checked both the adapter plugged into my vehicle and the trailer lights both work, but still nothing.  Has anyone had a similar issue?

Jammer

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Re: 4 pin wiring harness to my 7 pin trailer plug Problem
« Reply #1 on: November 30, 2012, 01:02:24 PM »
Don't go farther than the end of the parking lot without a brake controller and proper wiring.

Check the 4-way on your vehicle with a test light (not a meter), and check the ground on the 4-way too.  If it's all good be sure that the connectors on the 4-way are clean and bright.
2004 Suburban 2500 4wd 8.1 / 2010 Airstream Classic 30' /
1997 K2500 regular cab long bed pickup / 1971 Cayo C-11

COMer

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  • John & Darla
Re: 4 pin wiring harness to my 7 pin trailer plug Problem
« Reply #2 on: November 30, 2012, 07:54:58 PM »
Your 4-pin flat is not designed to handle brakes.  You would need your vehicle to have a brake controller installed and then a 7-pin connector to allow the brakes to work and for the trailer battery (if it has one) to be charged as you go down the road. 
John & Darla
Home near Erie, PA
Spend half the year with Campers on Mission

John From Detroit

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Re: 4 pin wiring harness to my 7 pin trailer plug Problem
« Reply #3 on: December 01, 2012, 10:22:47 AM »
4 pins are Right turn/stop, left turn/stop, tail/marker and ground (not necessarly in that order) the ground is the "Odd" pin.  Tail next to it and I'm ot sure which turn is which.

7 pin has those 4 plus brakes, battery and "AUX"

You can not adapt from 4 to 7 since the brakes won't work.

You need to upgrade the tow vehicle, adding a brake controller (Teknosha Prodiby?) and a battery charge lead and isolator system.
Nothing adds excitement like something that is none of your business
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riotstick

  • Posts: 1
Re: 4 pin wiring harness to my 7 pin trailer plug Problem
« Reply #4 on: April 28, 2013, 02:15:46 PM »
if the adapter is like mine, check the white wire for continuity...there was none. the white from the round end is designed to attach to the frame.

universe74

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Re: 4 pin wiring harness to my 7 pin trailer plug Problem
« Reply #5 on: May 10, 2013, 03:32:20 PM »
I am just getting my Curt 4to7 way (57676) installed in my Dakota.  Guy is just doing brakes.  Which wire charges the battery in the trailer? 

Icemaker

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Re: 4 pin wiring harness to my 7 pin trailer plug Problem
« Reply #6 on: May 10, 2013, 07:37:17 PM »
On my trailer it is Green=  turn/stop [passenger side]
                           Yellow= turn/stop [drivers side
                           Brown= running lights
                           White=  ground/frame

Seems to be standard, at least on my equipment.

George
George


94 Dolphin DP
99 CRV W/Blue Ox & Patriot Brakes
95 F-150 4X4 4.9
F420661
Fresno, Ohio most of the time

Alfa38User

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Re: 4 pin wiring harness to my 7 pin trailer plug Problem
« Reply #7 on: May 11, 2013, 10:41:28 AM »
Quote
I am just getting my Curt 4to7 way (57676) installed in my Dakota

Perhaps this will help:

Since you are using a 4 pin to 7 pin CONVERTER, like this:

http://www.curtmfg.com/part/57676

This might help select the correct pin-out:

http://howto.curtmfg.com/index.cfm.27.html

Looks like it would be the Auxiliary wire connection but you will have to wire it to the appropriate places on both trailer and vehicle. You do not have that wiring now if you have been using a 4 pin plug. There also seems to be some colour confusion between the Aux and Backup light terminals on the Curt charts but I would stick with the Aux pin designation, regardless of colours and wire things up accordingly.
« Last Edit: May 12, 2013, 08:03:34 AM by Alfa38User »
Stu
Montréal, Canada 🍁
Snowbird, Naples Florida
Alfa Gold 38 (2000) 5ver (parked!)

"Of course I talk to myself, sometimes I need expert advise!!!"

Icemaker

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Re: 4 pin wiring harness to my 7 pin trailer plug Problem
« Reply #8 on: May 12, 2013, 07:47:52 AM »
Thanks, I never could remember the other wire colors and plan to add a charging [power] pin to the 6way for my toad..
Now you've made it way easier for me to replace the 7way on my coach w/a 7way/4 flat and cover all towing situations..

Thanks again for those links..

George
George


94 Dolphin DP
99 CRV W/Blue Ox & Patriot Brakes
95 F-150 4X4 4.9
F420661
Fresno, Ohio most of the time

 

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